Expand.
Answer: We expand the parentheses using the distributive property : $ A(B+C)= A\cdot B+ A\cdot C$ We can also think about the problem using an area model: $-4t^3$ $8t^2$ $-t$ Here's how the solution goes, algebraically: $\begin{aligned} &\phantom{=}{-t}(-4t^3+8t^2) \\\\ &={-t}(-4t^3)+({-t})(8t^2) \\\\ &=4t^4-8t^3 \end{aligned}$ Here's how the solution looks in terms of the area model: $4t^4$ $-8t^3$ $-4t^3$ $8t^2$ $-t$ In conclusion, $-t(-4t^3+8t^2)=4t^4-8t^3$